Although there are certainly areas where they co-exist, I have another example...the KSC study site in east central Florida which has a very large breeding population of indigos, and lots of varied habitat from scrub and sandhills to canals, wetland...etc...The lead researcher on that project who has spent hundreds upon hundreds of hours in the field studying the indigos over a period of over 6 years, told me last year that she has NEVER seen a Florida king in the field in the entire study area!
Same situation in the SE GA study site, where the indigos abound...not a king snake to be found by the researchers who spend every day in the field collecting data. This is directly from the mouths of the folks who spend the time out there.
Up here...in central KY, you get corn snakes in large numbers in some areas, black kings in great numbers in others...similar habitat, but you almost never find them in the exact same spots.
It could be that some species in some regions have learned to avoid one another, and co-exist in others. It's a mystery...but then explain to me why the "coastal plains" milk is a scarlet king eastern milk integrade...while the 2 species co-exist in KY
with no evidence of integration?
oh, and...I don't want to go down that which snake would whip the other again...that issue has been beaten to death! 